So i purchased a Norco Team DH from 2005. It came with a DHX 3.0 on the rear shock. I was going to replace it with something different but was wondering if my Norco frame could use different size rear shocks? i see on the rear VPS section has a 8.2" and 9.1" printed on the frame where you can run the bottom of the shock and you can also move the upper mount to a lower position. I can't find any info about this VPS system at all. It's an older bike so im hoping someone might have an idea or some experience with this rig.

Thanks everyone.